<Image>.SaveJPEG (Function)

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<Image>.SaveJPEG (Function)

In french: <Image>.SauveJPEG

Saves an image:

in a JPEG file.
in memory.

This image corresponds to the image contained in a Image control.

Remarks:

Only the visible part of the Image control is saved.
This function can only be used to save the images for screen resolutions up to 32 bits.
This function cannot be used with the Image controls found in reports.
This function can also be used to save the changes made by ImageInfoModify on the Exif tags of an image.
Saving images in JPEG format is supported only if the application is run by the Java Virtual Machine (JVM) distributed by SUN. Images in JPEG format cannot be saved with other Java virtual machines.

Caution: Using this function under Linux requires a specific configuration.. For more details, see The drawings.

In browser code, this function can only be used to save an image in memory.

Example

// Sauve en mémoire l'image présente dans "IMG_ImageDessin"
ResSauvegarde = IMG_ImageDessin.SauveJPEG(inMemory)

// Sauve l'image présente dans "IMG_ImageDessin" sur "C:\Documents\Image.JPEG"
ResSauvegarde = IMG_ImageDessin.SauveJPEG("C:\Documents\Image.JPEG")

// Modification des commentaires de l'image
// affichée dans le champ Image "IMG_MonChampImage"
ImageInfoModify(IMG_MonChampImage, imgComment, "Belles gorgones")
// Enregistrement de la modification dans le 
// fichier "C:\Plongees\Gorgone1.JPG"
IMG_MonChampImage.SauveJPEG("C:\Plongees\Gorgone1.JPG", 100, imgSaveTag)

Syntax

Saving an image in a JPEG file Hide the details

<Result> = <Image control>.SaveJPEG(<File name> [, <Quality> [, <Exif tag>]])

<Result>: Boolean

True if the image was saved,
False otherwise. To get more details on the error, use ErrorInfo with the errMessage constant.

<Image control>: Control name

Name of the Image, Bar Code or Web Camera control to be used. Image controls in a report cannot be used.
Name of the Image or Web Camera control to be used.
Name of the Image control to be used.

<File name>: Character string

Name and full (or relative) path of JPEG file. A UNC path can be used. The file extension is optional.
Caution:
The destination directory must exist in order for the image to be saved.
The existence of the JPEG file is not checked. This file is automatically overwritten if it already exists.

<Quality>: Optional integer

Quality of the image saved. Value between 1 and 100 (80 by default). Lower image quality translates into higher image compression rate and smaller file size.

<Exif tag>: Optional constant (or combination of constants)

Save the Exif tags modified by ImageInfoModify:
imgAddThumbnail Adds a thumbnail into the image file (<File name>).
If there is a thumbnail in the image file displayed in the Image control, this constant is not taken into account.
This constant is not available.
imgGrayScale Used to save the image in black and white ("Grayscale" display mode).
This constant is not available.
imgProgressiveJPEG Saves the image in progressive JPEG format. This format is mainly used for the Web sites. It allows the pages to be loaded faster (the images being loaded and displayed progressively).
This constant is not available.
imgSaveTag Saves the Exif tags.
If there is a thumbnail in the image file displayed in the Image control, a new thumbnail is recalculated.
This constant can be used only if <Image name> is a variable of type Image. The thumbnail will not be recalculated.
This constant is not available.

By default, the Exif tags are not saved, no operation is performed on the thumbnails.
This parameter is not available.

Saving an image in memory Hide the details

<Result> = <Image control>.SaveJPEG(<inMemory> [, <Quality> [, <Exif tag>]])

<Result>: Buffer

Byte string containing the image in JPEG format.
Then this byte string can be assigned to an Image control, saved in a file (fSaveText), sent via a network (with the Socket functions), ...
In browser code, this byte string can only be assigned to another image ("Localize the image in the _WEB directory in browser code" must be unchecked). It cannot be saved in a file to build an image file.

<Image control>: Control name

Name of the Image, Bar Code or Web Camera control to be used. Image controls in a report cannot be used.
Name of the Image or Web Camera control to be used.
Name of the Image control to be used.

<inMemory>: Constant

inMemory: Constant used to save an image in memory.

<Quality>: Optional integer

Quality of the image saved. Value between 1 and 100 (80 by default). Lower image quality translates into higher image compression rate and smaller file size.

<Exif tag>: Optional constant (or combination of constants)

Save the Exif tags modified by ImageInfoModify:
imgAddThumbnail Adds a thumbnail into the image file (<File name>).
If there is a thumbnail in the image file displayed in the Image control, this constant is not taken into account.
This constant is not available.
imgProgressiveJPEG Saves the image in progressive JPEG format. This format is mainly used for the Web sites. It allows the pages to be loaded faster (the images being loaded and displayed progressively).
imgSaveTag Saves the Exif tags.
If there is a thumbnail in the image file displayed in the Image control, a new thumbnail is recalculated.
This constant is not available.

By default, the Exif tags are not saved, no operation is performed on the thumbnails.
This parameter is available only if <Control name> corresponds to the name of an Image control.
This parameter is not available.

Remarks

Image found in a Web Camera control

Only the image displayed when <Image>.SaveJPEG is executed is saved. To save this image, you can also use:

the <Camera>.Capture function: the image will be saved in BMP format
the <Image>.SaveBMP function: the image will be saved either in BMP format or in memory.
the <Image>.SaveGIF function: the image will be saved either in Gif format or in memory.
the <Image>.SavePNG function: the image will be saved either in PNG format or in memory.

Drawing in browser code

The image saved in memory can be directly assigned to an Image control. Depending on the browser used, the result may not be the expected one.

For example, with the current version of FireFox and Opera (available when this documentation was published), images in JPEG format are not displayed properly (they are displayed on a black background).

This operating mode may be improved during the next upgraded versions of these browsers.

Drawing in PHP

In PHP, the drawing functions are based on the graphic library GD. This library is commonly used by the PHP hosting providers and therefore it is always enabled. The version of the GD library must be version 2.0.28 (or later). This library can be downloaded from the PHP site.

To enable (if necessary) this library locally, the following elements are required:

PHP installed.
the PHP.INI file found in the Windows directory must contain the following line: "extension=php_gd2.dll" (instead of ";extension=php_gd2.dll").
the php_gd2.dll file must exist in the directory of PHP extensions. This directory is defined in the PHP.INI file by the "extension_dir" variable.

Component: wd300pnt.dll